In this section proposed algorithm is compared with existing round-robin algorithms for different cases. These comparisons take processes with different combination of burst time, priority and varying different time quantum. Proposed algorithm is compared with existing round-robin algorithms which are RoundRobin without Priority (RRWP), RoundRobin with Priority (RRP), ImprovisedRoundRobin (IRR). We compared our proposed algorithm with these three algorithms for about 50 times in different types of cases including all small burst time process, all large burst time process, and all medium burst time process and taking different combination of them. Eight of the cases are shown in Table 3. For each case minimum three different time quantum has been taken. So more than 24 numbers of comparisons have been shown here. Comparisons have been made for average waiting time, average context switch and average turnaround time. Comparison results are shown in Table 4 to Table 11.
1.2 Main Problem In RoundRobin Algorithm The processor in any computer receives many processes at the same time meaning that all those processes need to be handled regularly without leaving any one without processing. Roundrobin have a big problem in the concept of OS Scheduling its depended on priority that mean the processes are implemented based on FCFS. Every process have a high priority implement until it complete and do not have to delay for their next burst cycle. This paper attentions on decreasing the burst time of the traditional algorithm.
NoC router consists of virtual channel, arbiter and crossbar. For high performance of router, design a improving routing algorithm that provides conflict-free paths between input port and output port and require efficient arbiter that authorizes the requiring input port based on good scheduling mechanism. So it plays vital role in the design of NoC router. We have designed NoC router using roundrobin arbiter (RRA) based on fixed priority and dynamic adaptive arbiter (DAA) based on roundrobin mechanism to improve total NoC router performance.
user-friendliness. A project that is very close to our work is a simulator presented by (Padberg, 2003)  . However, this simulator was devised for a software project scheduling rather than CPU process scheduling, hence impertinent for our consideration in this study. MOSS  , Modern Operating Systems Simulators, it is a bible of Java-based simulation programs which illustrate key operating system concepts portrayed in a textbook by Tanenbaum (2001) for university students utilizing the text. This does not suit in to independent software that can be utilized freely without any such constraint. The best simulator we could find, so far, during our survey of previous related work was presented by (Cardella, 2002)  . It was developed in Visual Basic 6.0 and implemented the RoundRobin as a non-preemptive scheduling algorithm. It uses Average Completion Time (ACT) and Average Turn-around Times (ATT) as the criteria for performance evaluation. However, it is not as robust as ours in the sense that we implemented a Dynamic RoundRobin algorithm in addition to FCFS, SJF and ROUNDROBIN algorithms. Our major objective is to simulate the behavior of various CPUscheduling algorithms and to improve RoundRobinscheduling algorithm using dynamic time slice concept, called Dynamic RoundRobin, which calculates intelligent time slice and changes after every round of execution.
When many jobs are presented to Grids, they take overall processing including high overhead time and cost in terms of: to and from Grid resources, job transmission at Grid resources and job processing. CPU scheduler executes processes when they have schedules. The algorithm which decides order of execution when there are many processes in a ready queue is the scheduling algorithm. Various well known CPUscheduling algorithms are First Come First Serve (FCFS), Shortest Job First (SJF) and Priorityscheduling  all of which are non-pre emptive and unsuitable for time sharing systems. Shortest Remaining Time First (SRTF) and RoundRobin (RR) are pre-emptive in nature with RR being highly suitable for time sharing systems.
The Real-Time scheduling characteristics most nearly concerned with uncertainty; the execution or burst time of tasks and the umbrella category of real time constraints under which dead line, ready time, and task period fall. The most obvious place to introduce fuzzy concepts for modelling uncertainty in scheduling is with a task execution time. With this intent, the objective of present paper is to measure the performance of different CPUscheduling policies in fuzzy environment. The simulator designed accesses the performance of RoundRobin, Priority ( both pre-emptive and non pre-emptive) scheduling policies in terms of average waiting time and average turnaround time for a number of processes in uncertainty. In RoundRobin and PriorityCPUScheduling algorithm, the main concern is with the uncertainty in Burst Time and the increased waiting time and turnaround time. The decision for these is usually based on parameters which are assumed to be précised. However, in many cases, the values of these parameters are vague and imprecise rather than stochastic. Hence, considered fuzzy in nature. Ready queue is maintained in FCFS queue discipline.
Round–robin  is one of the algorithms employed by process and network scheduler in computing . As the term is generally used, time slices are assigned to each process in equal portions and in circular order, handling all processes without priority. Round-robinscheduling is simple, easy to implement. Round-robinscheduling can also be applied to other scheduling problems, such as data packet scheduling in computer networks. It is a system concept.
Packet scheduling algorithms enhances the packet delivery rate effectively in wireless networks; it helps to improve the quality of service of the wireless networks. Many algorithms had been deployed in the area of packet scheduling in wireless networks but less attention is paid to security. Some algorithms which offer security often compromise performances such as schedulability, this is not desirable. This performance problem will become worse when the system is under heavy load. In this paper we propose Roundrobinbased Secure- Aware Packet Scheduling algorithm (RSAPS) for wireless networks which focuses on secure scheduling. RSAPS is an adaptive algorithm which gives priority to scheduling when system is under heavy load. Under light load RSAPS provide maximum security for the incoming packets. Simulation has been performed using the proposed method and compared with existing algorithms SPSS and ISPAS. And it is found that RSAPS shows excellent scheduling quality holding the security levels.
compared to RED queues, especially in paths that have non- ECN compliant routers. Moreover, Modified RED (ModRED) does not require modification to TCP implementations at servers or clients Mod RED is based on the two-drop precedence policy. A packet is marked at the edge of the network as IN or OUT of its service contract and it is treated differently inside the network, on the basis of this priority classification. The router inside the network keeps just one queue for IN and OUT packets and apply to them two different RED algorithms as we can see in Figure 3.1. Instead of using the same average queue size for both priorities, it uses the average queue size for OUT (out of profile) packets, and the average queue size without taking into account the queued OUT packets for IN (in profile) packets. In time of congestion the router starts to drop OUT packets and eventually, if congestion persists, will start to discard IN packets, as well.
Another approach  has use FFGA (Fonseca and Fleming’s Genetic Algorithm) with the aim to improve QOS of existing CPUscheduling algorithm. The authors of this work incorporated three parameters of CPU burst time; I/O devices service time, and priority of process instead of using one parameter of CPU burst time. The designed approach selects an execution process according to the system condition. To show the effectiveness of proposed approach they have compared performance with the traditional FCFS, RR, SJF and Priority techniques. For the comparison they use FCFS and RR technique with equal, prioritized way and for SJF and Priority algorithm they implement with pre-emptive and nonpreemptive fashion. The simulation results have demonstrated that proposed method has optimizes the average waiting time and response time for the processes. A new preemptive CPU algorithm called SJRR  has introduced by different group of authors. The designed approach pre-empt the process on the base of their appearance time in ready queue. According to the authors of work their approach helps to improve the average waiting time of RoundRobin algorithm in real time uni-processor- multi programming operating system. They simulates designed approach along with traditional FCFS, RR and SJF technique for illustrating the benefits of new designed algorithm.
slice. In other words it determines which process runs when there are multiple runnable processes. As researchers  previously pointed out that the need for a scheduling algorithm arises from the requirement for fast computer systems to perform multitasking and multiplexing. CPUscheduling is important because it affects resource utilization and other performance parameters . Several CPUscheduling algorithms are available , , such as First Come First Serve Scheduling (FCFS), Shortest Job First Scheduling (SJF), Round-RobinScheduling (RR), and PriorityScheduling (PS). However, due to disadvantages, these algorithms are rarely used in shared time operating systems, except for RR Scheduling . RR is considered the most widely used scheduling algorithm in CPUscheduling ,  also used for flow passing scheduling through a network device . An essential task in operating systems in CPUScheduling is the process of allocating a specific process for a time slice. Scheduling requires careful attention to ensure fairness and avoid process starvation in the CPU. This allocation is carried out by software known as a scheduler , . The scheduler is concerned mainly with the following tasks :
Modern operating systems are moving towards multitasking environments in which fast computer systems perform multitasking (executing more than one process at a time) and multiplexing (transmitting multiple flows simultaneously). This mainly depends on the CPUscheduling algorithm as the CPU is the essential part of the computer. In computer science, scheduling is the act by which processes are given access to system resources (e.g., processor cycles, communications bandwidth). CPUscheduling is an essential operating system task which permits allocating the CPU to a specific process for a time slice. In other words it determines which process runs when there are multiple runnable processes. As researchers (Kopetz 2011) previously pointed out that the need for a scheduling algorithm arises from the requirement for fast computer systems to perform multitasking and multiplexing. CPUscheduling is important because it affects resource utilization and other performance parameters(Hasan). Several CPUscheduling algorithms are available (Silberschatz, Galvin et al. 2013), (Oyetunji and Oluleye 2009), such as First Come First Serve (FCFS), Shortest Job First Scheduling (SJF), Round-Robin (RR) Scheduling, and PriorityScheduling (PS). However, due to disadvantages, these algorithms are rarely used in shared time operating systems, except for RR Scheduling (Cerqueira and Brandenburg 2013).
In the recent past, a number of CPUscheduling mechanisms have been developed for predictable allocation of processor. Self- Adjustment Time Quantum in RoundRobin Algorithm  is based on a new approach called dynamic time quantum in which, time quantum is repeatedly adjusted according to the burst time of the running processes. Dynamic Quantum with Readjusted RoundRobinScheduling Algorithm  uses the job mix order for the algorithm in . According to , from a list of N processes, the process which needs minimum CPU time is assigned the time quantum first and then highest from the list and so on till the Nth process. Again in the 2nd round, the time quantum is calculated from the remaining CPU burst time of the processes and is assigned to the processes and so on. Both  and  are better than RR scheduling and overcomes the limitations of RR scheduling regarding the average waiting time, average turnaround time and context switch. Algorithm in  uses an approximation of K-means clustering algorithm to group processes of same kind together and dispatches them to appropriate processor. A new fair-share scheduling with weighted time slice  assigns a weight to each process and the process having the least burst time is assigned the largest weight. The time quantum is calculated dynamically, using weighted time slice method and then the processes are executed.  calculates the original time slice suited to the burst time of each processes and then dynamic ITS (Intelligent Time Slice) is found out in conjunction with the SRTN algorithm. Algorithm in  is improved by using dynamic time quantum and multi cyclic time quantum.
The time sliced and prioritybased algorithm is better compared to roundrobin and equally spread current execution load balancing algorithm with respect to waiting time and turnaround time. The context switching is also reduced. The improvement in the performance can be noted when the algorithms are run with different routing policies. The disadvantage is sometimes, the task with high priority may be the last to execute. High priority jobs at times have to wait based on the time slice. In future an algorithm should be developed which will reduce the starvation time of the jobs with higher priority.
Operating System is a collection of software modules to assist programmers in enhancing system efficiency and robustness. It is an extended machine from the user’s point of view & a resource manager from the system point of view. Scheduling is the most repetitively used fundamental concept in OS. In multitasking and multiprogramming environment it is necessary to choose the process among the number of process present in the job pool according to their need. Allocation of CPU to the processes is done by scheduler, which operated by some scheduling algorithms. FCFS, SJF, Priority & RR are different type of scheduling algorithms. In which RR is the most popular non-preemptive scheduling algorithm. In non- preemption, CPU is assigned to a process until its execution is completed. But in preemption, running process is forced to release the CPU by the newly arrived process[8,9]. Each scheduling algorithm has its own advantages and disadvantages. Similarly RR has a drawback which increase average waiting time, average turnaround time and minimizes the throughput, known as Context switch. The processes in RR are assigned with a time quantum which is static by nature.
Roundrobin is one of the mostly used scheduling algorithms which have equal priority of every process. In this system, every process is preempted after a specified time quantum or time slice. Although RR gives improved response time and uses shared resources efficiently . Larger waiting time, undesirable overhead and larger turnaround time for processes with variable CPU bursts due to the use of static time quantum, etc. are the limitations for RR. In this case a RR with progressive time quantum on the sorted ready queue can be developed. RoundRobin works with a small unit of time for the execution of process which is called Time Quantum or Time slice. If a process CPU burst exceeds 1-time quantum, that process is preempted and is put back in the ready queue. If a new process arrives then it is added to the tail of the circular queue. However, RR provides better performance among the above discussed algorithms as compared to the others in the case of the time sharing operating system. It works with a fixed time slice. All the existing works based on RoundRobin edit the way of taking time slice. But among them, different way shows different limitations. When the time slice is too high the process in the ready queue are suffering from starvation . When it is very small the context switching time is high.
resources. After a vast advancement of technology, the cost of hardware get reduced to affordable price and the interest of author turned to fast calculation and response. The system is controlled by the multiprogramming and multitasking approach of operating system. The CPU plays an important role in implementation of multipro- gramming and multitasking . The use of computer has affected most of the working of our daily life and the use in almost all sort of field has invited a number of applications for every level of users. As many applications worked simultaneously which required many numbers of processes to be created, the processes must be exe- cuted in such a manner to provide the better response to users. The increment of processes in the system in- creased the responsibility of CPU scheduler. The users expect fast response and execution, and users’ expecta- tion results in a requirement of least waiting time in execution. There exist a number of scheduling algorithms   but RoundRobin, Shortest Remaining Time First and the Priorityscheduling may have the weightage of the most widely used scheduling algorithms. They have their advantages and disadvantages too. The concept of de- signing a scheduling algorithm has a significant age around thirty years; even then we are motivated to found some scope of improvement in the CPUscheduling approach. We believe that there always exists some hope where normal people found dead, because it depends on the view of researchers. A significant work has been done by many researchers over last two decades but we find a new hope and through this paper a new schedul- ing algorithm Varying Response Ratio Priority is introduced. In this paper, we have tried to collect the advan- tage of Shortest Remaining Time First and Priority by merging them and to eliminate the starvation condition by using indirect aging. In this scheduling algorithm for new processes the decision of allocating the CPU depends similarly as in shortest remaining time first and for the old processes waiting in ready queue decision gets af- fected by the ratio of waiting time and remaining burst time. The main objective of this paper is to provide the scheduling without starvation and average waiting time if not equal to but nearer to the average waiting time of shortest remaining time first. In this manuscript, we use the deterministic model to compare the VRRP to other scheduling algorithms. The next section contains the brief description of some of the most common scheduling algorithms. In Section 3, we have explained the working and calculation of our approach. Section 4 explains the comparative results with some most favourite scheduling and finally our conclusion comes in the Section 5.
n an operating system, a large number of processes arrive to the scheduler whose role is to manage the processing of these jobs. There are many scheduling schemes available in literature [see Silberschatz and Galvin , Stalling , Tanenbaum and Woodhull ] like FIFO, Roundrobin, Prioritybased, Multi-level queue and so on. All these have some advantages and disadvantages over each other. A unified study for scheduling scheme is required under a common environment. This motivates to design a general class of scheduling schemes so that its member may possess common properties of the class as well as could be mutually compared. With this thought of motivation, a general class of scheduling scheme is designed in this paper containing some well-known schemes like FIFO and Roundrobin as member schemes.
Scheduling in operating systems is allocate certain amount of CPU time with use of different processes. Task scheduling is also one of the key process in running of different processors in with in life time. RoundRobin (RR) is a popular scheduling algorithm allows to utilize the CPU short time for individual task scheduling events in real time process execution. The advancement of RR scheduling performs fine tuning for time slice which do not stipulated time to allocate them in events proceedings based on CPUscheduling. RR also maintains turnaround time, waiting time and response time with processing frequency of context switches. In this paper we improve the performance of RR with integer programming to refine in arrival time analysis in process scheduling with proceedings of all the requirement CPU processes. Every process has reasonable response and arrival time analysis in allocation of scheduling in process allocation. A method the usage of integer programming has been proposed to resolve equations that determine Changeable Time Quantum (CTQ) value that is neither too massive nor too small such that each system has reasonable response time and the throughput of the system is not decreased because of unnecessarily context switches.
Scheduling is already part of a parallel process . In scheduling, there are several methods used to perform queue process that comes to the processor. Some algorithms are popular among other First Come First Serve, Shortest Job First, and RoundRobin. In this study, The discussion involves the comparison of the average waiting time of each of these algorithms. The purpose of this comparison to determine what algorithm is more suitable for some processes that are in the ready queue. The priority of the processes that occur on the processor is something that determines when the process will be done. However, it does not discuss the priority in this study. The scheduling assumes all of which occurred in the queue have the same priority value.